Most optoelectronic systems include hermetic packages. Active components such as semi-conductor lasers or other gain media typically perform better in a controlled atmosphere. Passive components, such as thin film dielectric filters are susceptible to humidity changes, for example.
The typical hermetic package comprises a frame defining the hermetic boundary. This frame typically includes a base, sidewalls, and a lid. The lid is typically welded or otherwise sealed to the tops of the sidewalls as one of the final steps in the packaging process.
The frames further typically comprise optical and electrical feedthroughs. The optical, or fiber, feedthroughs are usually in the form holes in the sidewalls of the frame that accommodate the insertion of fiber optic pigtails through the holes and into the packages. During manufacture, the optical fiber pigtails are installed onto optical benches, or submounts, within the frames. The electrical feedthrough typically comprises an assembly that provides mutually isolated electrical connections between wire bond areas within the frame and electrical contacts that are outside of the frame. Typically, dual in-line package (DIL) or butterfly style leads are then attached to the electrical contact areas to electrically connect the package to a circuit board, for example.